docs: def update_hints(obj, data):
      """Update the hints on the root-node of a workflow. Usually, schedule
      hints are fixed per function. Sometimes a user may want to set hints
      manually on a specific promised object. :func:`update_hints` uses the
      `update` method on the hints dictionary with `data` as its argument.
  
      :param obj: a :py:class:`PromisedObject`.
      :param data: a :py:class:`dict` containing additional hints.
  
      The hints are modified, in place, on the node. All workflows that contain
      the node are affected."""
      root = obj._workflow.root
      obj._workflow.nodes[root].hints.update(data)